Major Depression and Bipolar Disorder: The Concept of Symmetry Breaking

In this paper we consider the results obtained by biochemical experimental data on platelet membrane fatty acids processed by a Self Organizing Map (SOM) from apparently healthy, bi-polar (BD) and major depressive subjects (MDD). The SOM shows that major depressive subjects belong to an area which is completely disconnected from that of healthy and bi-polar. Looking at the location of the data over the SOM, we find also a region which we attribute to psychotic subjects according to the clinical diagnosis. We translated these facts in terms of symmetry breaking, confirming that MDD is a disease completely trapped apart from healthy, bi-polar, and psychotic subjects.